湿法冶金工艺提铌现状与展望  

Current state and future possibilities for niobium extraction via hydrometallurgy

作　　者：田丛众 邹文杰 刘凤阳 路雨馨 李正要 张志军[2] TIAN Congzhong;ZOU Wenjie;LIU Fengyang;LU Yuxin;LI Zhengyao;ZHANG Zhijun(School of Civil and Resources Engineering,University of Science and Technology Beijing,Beijing 100083,China;School of Chemical and Environmental Engineering,China University of Mining and Technology-Beijing,Beijing 100083,China)

机构地区：[1]北京科技大学土木与资源工程学院,北京100083 [2]中国矿业大学(北京)化学与环境工程学院,北京100083

出　　处：《中国有色金属学报》2024年第10期3435-3451,共17页The Chinese Journal of Nonferrous Metals

基　　金：国家重点研发计划资助项目(2022YFC2905302);国家自然科学基金资助项目(52174236)。

摘　　要：铌具有耐高温、耐腐蚀、超导性好等优良特性,是现代工业中不可或缺的关键原材料。湿法冶金是生产高纯铌产品(纯度>99.5%)的主要工艺。HF能将90%铌矿分解,但仅适用于高品位铌矿,工业生产中多采用H_(2)SO_(4)-HF二元浸出体系,在使用H_(2)SO_(4)浸出铌矿时需严格控制H_(2)SO_(4)浓度和矿石中硅质和钙质脉石的含量,草酸等有机羧酸也可减少对HF的依赖,但单独使用效果较差。碱性介质分解工艺用钾盐和钠盐分解铌矿,可用于处理低品位铌矿,但存在碱消耗量大及对设备要求高等弊端。亚熔盐法可提高铌矿分解效率并减少碱的消耗,有望实现低品位铌矿的高效提取。在铌矿浸出液的萃取分离中,MIBK、TBP、CHO和2-OCL是4种商业化萃取剂,存在依赖HF、溶剂损失大、萃取效果波动大等不足;离子交换工艺研究较少,却有望用于低浓度铌矿浸出液的提取;化学沉淀工艺常用于萃取后富液的处理,将可溶性铌盐转化为沉淀再经过煅烧获得铌产品,该工艺选择性较差,产品纯度较低。未来应着力开发高效选冶联合和火法湿法联合工艺,开展铌矿分解和浸出的动力学研究,探明影响铌矿分解的控制性步骤,开发针对低浓度铌矿浸出液的高效、低耗和高选择性提取工艺。As one of critical materials in modern industry,niobium(Nb)has exceptional properties like resistance to high temperature and corrosion as well as superconductivity.Hydrometallurgical treatments are the mainly adopted technique to produce niobium product with purity of above 99.5%.Being able to dissolve approximately 90%Nb ores,however,HF only suits the high-grade.In industry,HF-H_(2)SO_(4) binary system is widely adopted.When leaching Nb ores using H_(2)SO_(4),careful controls of H_(2)SO_(4)concentration and gangues bearing silicium and calcium are essential.Despite the decreased use of HF in the presence of carboxylic acid,its effect in dissolving Nb ores directly is unsatisfactory.Alkaline dissolution using potassium and sodium salts as leachants or fluxes is capable to treat low grade Nb ores.However,its application is limited by the large consumption of alkaline agent and severe equipment corrosion.Sub-molten salt leaching could overcome these drawbacks thus exhibiting promising potential to tackle low grade Nb ores.For extracting Nb from leaching solution,MIBK,TBP,CHO and 2-OCL are four types of commercialized extractants,while they have several disadvantages,referring to dependence on HF,great mass loss and low adoptability to impurities.Though modest concentration having attracted in Nb recovery,ion exchange is a promising technique to extract Nb from leaching solution.Precipitation along with calcination are commonly employed to treat Nb-enriched solution,nevertheless,the quality of final production is low due to the poor selectivity during this procedure.From future perspectives,worthy efforts should be devoted to developing combined treatments consisting of separation-smelting as well as pyrometallurgy-hydrometallurgy.It is also recommended to study the kinetics and ascertain the controlling steps during dissolution and leaching procedures.For low grade Nb leaching solutions,extraction strategies with high efficiency,low energy consumption and high selectivity are expected.

关 键 词：铌矿 低品位 湿法冶金 提取 联合工艺 

分 类 号：TF841[冶金工程—有色金属冶金]